A new class of optical metamaterials is attracting great attention: metasurfaces, which are ultrathin twodimensional structures that diversely manipulate light. Metasurfaces ease fabrication difficulty and avoid the influence of absorption loss in metals more than three-dimensional optical metamaterials. In particular, the recent development of nanoimprint lithography technologies is increasing the possibility of practical applications of metasurfaces. Metasurfaces manipulate light waves with a huge degree of freedom, and also enhance various optical processes through the high local density of the states of radiation fields. We introduce recent progress in light-emitting optical metasurfaces that exhibit a large enhancement of thermal emission and fluorescence.